Bug 812729

Summary: The volume name is different from the device name
Product: [Fedora] Fedora Reporter: Xiaowei Li <xiaoli>
Component: lvm2Assignee: LVM and device-mapper development team <lvm-team>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 17CC: agk, bmarzins, bmr, dwysocha, extras-orphan, heinzm, jonathan, lvm-team, mbroz, msnitzer, prajnoha, prockai, qcai, zkabelac
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2012-04-16 07:04:59 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description Xiaowei Li 2012-04-16 06:11:03 UTC 
Description of problem:


Version-Release number of selected component (if applicable):


How reproducible:
always

Steps to Reproduce:
1.# lvcreate -l 254 -T vg3/pool-01
2.# ls -l /dev/mapper/vg3*
lrwxrwxrwx. 1 root root 8 Apr 16 02:05 /dev/mapper/vg3-pool--01 -> ../dm-45
lrwxrwxrwx. 1 root root 8 Apr 16 02:05 /dev/mapper/vg3-pool--01_tdata -> ../dm-43
lrwxrwxrwx. 1 root root 8 Apr 16 02:05 /dev/mapper/vg3-pool--01_tmeta -> ../dm-42
lrwxrwxrwx. 1 root root 8 Apr 16 02:05 /dev/mapper/vg3-pool--01-tpool -> ../dm-44

3.# lvs vg3
  LV      VG   Attr     LSize    Pool Origin Data%  Move Log Copy%  Convert
  pool-01 vg3  twi-a-tz 1016.00m               0.00    
  
Actual results:
/dev/mapper/vg3-pool--01


Expected results:
/dev/mapper/vg3-pool-01


Additional info:
Comment 1 Xiaowei Li 2012-04-16 06:12:31 UTC 
this issue was encountered if the lv name has '-'
Comment 2 Peter Rajnoha 2012-04-16 07:04:59 UTC 
This is not a bug. The '-' character is doubled if it's part of the volume name (or volume group name). The character is escaped this way because, otherwise, the '-' character alone is considered as a delimiter between a VG name and an LV name.
Comment 3 Alasdair Kergon 2012-04-16 15:19:39 UTC 
The supported form for other software to use is '/dev/vg3/pool-01'.

/dev/mapper/* and /dev/dm-* are considered private internal names.
Comment 4 Alasdair Kergon 2012-04-16 15:21:46 UTC 
(And in the case of thin pools, they will usually be considered private and not meant to be used by other software, so not available under /dev/vg*.)